[pinkphiloyd]

Anybody have any tips?  Color perhaps?  Our final product was dark red.  We're quite sure from NMR that it's not 1,1'.  But we're having trouble determining if it's 1,2 or 1,3.  We didn't realize until we were out of product that melting point would have been of use.

[Mitch]

What do you mean by 1,1'

[pinkphiloyd]

What do you mean by 1,1'

Ferrocene consists of an iron ion "sandwiched" between two 5 carbon rings.  When undergoing Friedel-Crafts acylation, if both of the acetyl groups wind up on one ring, they have two options for arrangement, 1,2 or 1,3.  If, however, one acetyl group goes to each 5 carbon ring, the acetyl substituents are said to be 1,1'.

[macman104]

If it's 1,2 you'll only have 2 different types of hydrogens on the carbon rings.  If it's 1,3 you should have 3 different types.

[sjb]

What do you mean by 1,1'

1,1' means that there is an acetyl group on each of the Cp rings

S

[macman104]

If it's 1,2 you'll only have 2 different types of hydrogens on the carbon rings.  If it's 1,3 you should have 3 different types.

I wanted to add that I believe this to be true, but I'm not sure if there is any interaction between hydrogens between the two rings.

[pinkphiloyd]

Thanks everybody.  I felt dumb as soon as the answer to this hit me.  We didn't wind up with 1,2 or 1,3.  Due to the deactivating tendency of the first acetyl group, the second always goes onto the other ring.  Thankfully, this hit me before my lab report was due!